1. Field of the Invention
The present invention relates to a method of treating respiratory viral infections, compositions useful for treating and/or preventing respiratory viral infections, and apparatus for delivering such compositions. The present invention also relates to methods of treating herpesvirus infection and hepadnavirus infection.
2. Discussion of the Background
Respiratory viral infections are an important cause of respiratory disease. Examples of such respiratory diseases arising from viral infection include influenza A, influenza B, and respiratory syncytial virus (RSV).
There are a number of drugs available for such respiratory viral infections, including ribavirin, amantadine, and rimantadine. However, none of these therapies are completely satisfactory. In particular, such drugs may be accompanied by side effects including nausea, hematological toxicity, and the development of resistant viruses.
Polyoxometalates are soluble inorganic cluster-like compounds formed principally of oxide anion and early transition metal cations. Some major polyoxometalate structural families are as follows: (1) the Keggin class (e.g., .alpha.-SiW.sub.12 O.sub.40.sup.4-); (2) the Wells-Dawson class (e.g., P.sub.2 W.sub.18 O.sub.62.sup.6-); (3) fragments from these structures (e.g., PW.sub.11 O.sub.39.sup.7-); (4) the Keggin derived sandwich compounds (e.g., K.sub.10 Fe.sub.4 (H.sub.2 O).sub.2 (PW.sub.9 O.sub.34).sub.2, code name, HS058); (5) the hexametalates or the Lindquist class (e.g., W.sub.6 O.sub.19.sup.2-), decatungstate (W.sub.10 O.sub.32.sup.4-); and (6) the Preyssler ion [(NaP.sub.5 W.sub.30 O.sub.114).sup.14- ] (Hill, C. L., et al, J. Med. Chem, vol. 33, pp. 2767-2772 (1990); Hill, C. L., et al, in Advances in Chemotherapy of AIDS, Diasio, R. B., et al, Eds, Pergamon Press, New York, pp. 33-41 (1990).
The potent and selective anti-human immunodeficiency virus type-1 (HIV-1) activity of polyoxometalates in infected human peripheral mononuclear (PBM) cells or cultured CD4+ T-cell lines has been reported by several workers. (Hill, C. L., et al, J. Med. Chem, vol. 33, pp. 2767-2772 (1990); Hill, C. L., et al, in Advances in Chemotherapy of AIDS, Diasio, R. B., et al, Eds, Pergamon Press, New York, pp. 33-41 (1990); Kim, G.-S., et al, J. Med. Chem., vol. 37 (1994), Yamamoto, N. et al, Mol. Pharmacol., vol. 42, pp. 1109-1117 (1992). Polyoxometalates have also been shown to be broadly inhibitory against retro-, myxo-, herpes-, toga-, rhabdo- and arenaviruses replications in vitro (Ikeda S. et al, Antiviral Chem. Chemother., vol. 4, pp. 253-262 (1993); Yamamoto, N. et al, Mol. Pharmacol., vol. 42, pp. 1109-1117 (1992). The mechanism of anti-HIV action may be attributed to inhibition of virus cell binding and inhibition of syncytium formation (Hill, C. L., et al, J. Med. Chem, vol. 33, pp. 2767-2772 (1990); Kim, G.-S. et al, Unpublished work; Take, Y., et al, Antiviral Res., vol. 15, pp. 113-124 (1991). A similar mechanism of antiviral action has also been suggested against influenza virus (FluV)-A and respiratory syncytial virus (RSV) (Ikeda S. et al, Antiviral Chem. Chemother., vol. 4, pp. 253-262 (1993).
However, to date, there is no report of the treatment of respiratory viral infection by the administration of a polyoxometalate. Thus, there remains a need for a method of treating respiratory viral infections. There also remains a need for compositions and apparatus useful for treating respiratory viral infections. There also remains a need for treating human herpesvirus infections and hepadnavirus infections.